The FrΓ©chet derivative: congruence properties #
Lemmas about congruence properties of the Frechet derivative under change of function, set, etc.
Tags #
derivative, differentiable, FrΓ©chet, calculus
congr properties of the derivative #
theorem
hasFDerivWithinAt_congr_set'
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{f' : E βL[π] F}
{x : E}
{s t : Set E}
(y : E)
(h : s =αΆ [nhdsWithin x {y}αΆ] t)
:
theorem
hasFDerivWithinAt_congr_set
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{f' : E βL[π] F}
{x : E}
{s t : Set E}
(h : s =αΆ [nhds x] t)
:
theorem
differentiableWithinAt_congr_set'
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{x : E}
{s t : Set E}
(y : E)
(h : s =αΆ [nhdsWithin x {y}αΆ] t)
:
theorem
differentiableWithinAt_congr_set
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{x : E}
{s t : Set E}
(h : s =αΆ [nhds x] t)
:
theorem
fderivWithin_congr_set'
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{x : E}
{s t : Set E}
(y : E)
(h : s =αΆ [nhdsWithin x {y}αΆ] t)
:
theorem
fderivWithin_congr_set
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{x : E}
{s t : Set E}
(h : s =αΆ [nhds x] t)
:
theorem
fderivWithin_eventually_congr_set'
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{x : E}
{s t : Set E}
(y : E)
(h : s =αΆ [nhdsWithin x {y}αΆ] t)
:
theorem
fderivWithin_eventually_congr_set
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{x : E}
{s t : Set E}
(h : s =αΆ [nhds x] t)
:
theorem
Filter.EventuallyEq.hasStrictFDerivAt_iff
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{fβ fβ : E β F}
{fβ' fβ' : E βL[π] F}
{x : E}
(h : fβ =αΆ [nhds x] fβ)
(h' : β (y : E), fβ' y = fβ' y)
:
theorem
HasStrictFDerivAt.congr_fderiv
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{f' g' : E βL[π] F}
{x : E}
(h : HasStrictFDerivAt f f' x)
(h' : f' = g')
:
HasStrictFDerivAt f g' x
theorem
HasFDerivAt.congr_fderiv
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{f' g' : E βL[π] F}
{x : E}
(h : HasFDerivAt f f' x)
(h' : f' = g')
:
HasFDerivAt f g' x
theorem
HasFDerivWithinAt.congr_fderiv
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f : E β F}
{f' g' : E βL[π] F}
{x : E}
{s : Set E}
(h : HasFDerivWithinAt f f' s x)
(h' : f' = g')
:
HasFDerivWithinAt f g' s x
theorem
HasStrictFDerivAt.congr_of_eventuallyEq
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{f' : E βL[π] F}
{x : E}
(h : HasStrictFDerivAt f f' x)
(hβ : f =αΆ [nhds x] fβ)
:
HasStrictFDerivAt fβ f' x
theorem
Filter.EventuallyEq.hasFDerivAtFilter_iff
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{fβ fβ : E β F}
{fβ' fβ' : E βL[π] F}
{x : E}
{L : Filter E}
(hβ : fβ =αΆ [L] fβ)
(hx : fβ x = fβ x)
(hβ : β (x : E), fβ' x = fβ' x)
:
theorem
HasFDerivAtFilter.congr_of_eventuallyEq
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{f' : E βL[π] F}
{x : E}
{L : Filter E}
(h : HasFDerivAtFilter f f' x L)
(hL : fβ =αΆ [L] f)
(hx : fβ x = f x)
:
HasFDerivAtFilter fβ f' x L
theorem
Filter.EventuallyEq.hasFDerivAt_iff
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{fβ fβ : E β F}
{f' : E βL[π] F}
{x : E}
(h : fβ =αΆ [nhds x] fβ)
:
theorem
Filter.EventuallyEq.differentiableAt_iff
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{fβ fβ : E β F}
{x : E}
(h : fβ =αΆ [nhds x] fβ)
:
theorem
Filter.EventuallyEq.hasFDerivWithinAt_iff
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{fβ fβ : E β F}
{f' : E βL[π] F}
{x : E}
{s : Set E}
(h : fβ =αΆ [nhdsWithin x s] fβ)
(hx : fβ x = fβ x)
:
theorem
Filter.EventuallyEq.hasFDerivWithinAt_iff_of_mem
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{fβ fβ : E β F}
{f' : E βL[π] F}
{x : E}
{s : Set E}
(h : fβ =αΆ [nhdsWithin x s] fβ)
(hx : x β s)
:
theorem
Filter.EventuallyEq.differentiableWithinAt_iff
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{fβ fβ : E β F}
{x : E}
{s : Set E}
(h : fβ =αΆ [nhdsWithin x s] fβ)
(hx : fβ x = fβ x)
:
theorem
Filter.EventuallyEq.differentiableWithinAt_iff_of_mem
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{fβ fβ : E β F}
{x : E}
{s : Set E}
(h : fβ =αΆ [nhdsWithin x s] fβ)
(hx : x β s)
:
theorem
HasFDerivWithinAt.congr_mono
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{f' : E βL[π] F}
{x : E}
{s t : Set E}
(h : HasFDerivWithinAt f f' s x)
(ht : Set.EqOn fβ f t)
(hx : fβ x = f x)
(hβ : t β s)
:
HasFDerivWithinAt fβ f' t x
theorem
HasFDerivWithinAt.congr
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{f' : E βL[π] F}
{x : E}
{s : Set E}
(h : HasFDerivWithinAt f f' s x)
(hs : Set.EqOn fβ f s)
(hx : fβ x = f x)
:
HasFDerivWithinAt fβ f' s x
theorem
HasFDerivWithinAt.congr'
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{f' : E βL[π] F}
{x : E}
{s : Set E}
(h : HasFDerivWithinAt f f' s x)
(hs : Set.EqOn fβ f s)
(hx : x β s)
:
HasFDerivWithinAt fβ f' s x
theorem
HasFDerivWithinAt.congr_of_eventuallyEq
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{f' : E βL[π] F}
{x : E}
{s : Set E}
(h : HasFDerivWithinAt f f' s x)
(hβ : fβ =αΆ [nhdsWithin x s] f)
(hx : fβ x = f x)
:
HasFDerivWithinAt fβ f' s x
theorem
HasFDerivAt.congr_of_eventuallyEq
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{f' : E βL[π] F}
{x : E}
(h : HasFDerivAt f f' x)
(hβ : fβ =αΆ [nhds x] f)
:
HasFDerivAt fβ f' x
theorem
DifferentiableWithinAt.congr_mono
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s t : Set E}
(h : DifferentiableWithinAt π f s x)
(ht : Set.EqOn fβ f t)
(hx : fβ x = f x)
(hβ : t β s)
:
DifferentiableWithinAt π fβ t x
theorem
DifferentiableWithinAt.congr
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(h : DifferentiableWithinAt π f s x)
(ht : β x β s, fβ x = f x)
(hx : fβ x = f x)
:
DifferentiableWithinAt π fβ s x
theorem
DifferentiableWithinAt.congr_of_eventuallyEq
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(h : DifferentiableWithinAt π f s x)
(hβ : fβ =αΆ [nhdsWithin x s] f)
(hx : fβ x = f x)
:
DifferentiableWithinAt π fβ s x
theorem
DifferentiableWithinAt.congr_of_eventuallyEq_of_mem
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(h : DifferentiableWithinAt π f s x)
(hβ : fβ =αΆ [nhdsWithin x s] f)
(hx : x β s)
:
DifferentiableWithinAt π fβ s x
theorem
DifferentiableWithinAt.congr_of_eventuallyEq_insert
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(h : DifferentiableWithinAt π f s x)
(hβ : fβ =αΆ [nhdsWithin x (insert x s)] f)
:
DifferentiableWithinAt π fβ s x
theorem
DifferentiableOn.congr_mono
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{s t : Set E}
(h : DifferentiableOn π f s)
(h' : β x β t, fβ x = f x)
(hβ : t β s)
:
DifferentiableOn π fβ t
theorem
DifferentiableOn.congr
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{s : Set E}
(h : DifferentiableOn π f s)
(h' : β x β s, fβ x = f x)
:
DifferentiableOn π fβ s
theorem
differentiableOn_congr
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{s : Set E}
(h' : β x β s, fβ x = f x)
:
theorem
DifferentiableAt.congr_of_eventuallyEq
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
(h : DifferentiableAt π f x)
(hL : fβ =αΆ [nhds x] f)
:
DifferentiableAt π fβ x
theorem
DifferentiableWithinAt.fderivWithin_congr_mono
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s t : Set E}
(h : DifferentiableWithinAt π f s x)
(hs : Set.EqOn fβ f t)
(hx : fβ x = f x)
(hxt : UniqueDiffWithinAt π t x)
(hβ : t β s)
:
theorem
Filter.EventuallyEq.fderivWithin_eq
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(hs : fβ =αΆ [nhdsWithin x s] f)
(hx : fβ x = f x)
:
theorem
Filter.EventuallyEq.fderivWithin_eq_of_mem
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(hs : fβ =αΆ [nhdsWithin x s] f)
(hx : x β s)
:
theorem
Filter.EventuallyEq.fderivWithin_eq_of_insert
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(hs : fβ =αΆ [nhdsWithin x (insert x s)] f)
:
theorem
Filter.EventuallyEq.fderivWithin'
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s t : Set E}
(hs : fβ =αΆ [nhdsWithin x s] f)
(ht : t β s)
:
theorem
Filter.EventuallyEq.fderivWithin
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(hs : fβ =αΆ [nhdsWithin x s] f)
:
theorem
Filter.EventuallyEq.fderivWithin_eq_of_nhds
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(h : fβ =αΆ [nhds x] f)
:
@[deprecated Filter.EventuallyEq.fderivWithin_eq_of_nhds (since := "2025-05-20")]
theorem
Filter.EventuallyEq.fderivWithin_eq_nhds
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(h : fβ =αΆ [nhds x] f)
:
theorem
fderivWithin_congr
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(hs : Set.EqOn fβ f s)
(hx : fβ x = f x)
:
theorem
fderivWithin_congr'
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
{s : Set E}
(hs : Set.EqOn fβ f s)
(hx : x β s)
:
theorem
Filter.EventuallyEq.fderiv_eq
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
(h : fβ =αΆ [nhds x] f)
:
theorem
Filter.EventuallyEq.fderiv
{π : Type u_1}
[NontriviallyNormedField π]
{E : Type u_2}
[NormedAddCommGroup E]
[NormedSpace π E]
{F : Type u_3}
[NormedAddCommGroup F]
[NormedSpace π F]
{f fβ : E β F}
{x : E}
(h : fβ =αΆ [nhds x] f)
: